<template>
  <div class="login_box">
    <!-- 头像区域 -->
    <div class="avatar_box">
      <img src="../../assets/images/logo.jpg" alt="">
    </div>
    <!-- 登陆表单区域 -->
    <el-form ref="loginFormRef" :model="loginForm" :rules="loginFormRules" label-width="0px" class="login_from">
    <!-- 用户名 -->
      <el-form-item prop="username">
        <el-input v-model="loginForm.username" prefix-icon="iconfont icon-user"></el-input>
      </el-form-item>
      <!-- 密码 -->
      <el-form-item prop="password">
        <el-input v-model="loginForm.password" prefix-icon="iconfont icon-lock_fill" type="password"></el-input>
      </el-form-item>
      <!--  按钮区域  -->
      <el-form-item class="btn">
        <el-button type="primary" @click="loginClick">登陆</el-button>
        <el-button type="info" @click="resetLoginForm">重置</el-button>
      </el-form-item>
    </el-form>
  </div>
</template>

<script>
  export default {
    name: "LoginItem",
    data() {
      return {
        // 这是登陆表单的数据绑定对像
        loginForm: {
          username: 'admin',
          password: '123456'
        },
        // 表单验证规则对像
        loginFormRules: {
          // 验证用户名是否合法
          username: [
            {required: true, message: "请输入用户名", trigger: "blur"},
            {min: 3, maX: 10, message: "长度在3到10个字符", trigger: "blur"}
          ],
          // 验证密码是否合法
          password: [
            {required: true, message: "请输入密码", trigger: "blur"},
            {min:6, max: 16, message: "长度在6到16个字符", trigger: "blur"}
          ]
        }
      }
    },
    methods: {
      // 点击重置按钮
      resetLoginForm() {
        this.$refs.loginFormRef.resetFields();
      },
      // 表单预验证
      loginClick() {
        this.$refs.loginFormRef.validate(async valid => {
          if(!valid) return;
          const { data: res } = await this.$http.post('login', this.loginForm)
          if (res.meta.status !== 200) return this.$message.error('登录失败！')
          this.$message.success('登陆成功！')
          // 1. 将登陆成功之后的taken,保存到客户端的sessionStorage中
          //    1.1 项目中除了登陆之外的其他API接口，必须在登陆之后才能访问
          //    1.2 token只应在当前网站打开期间生效，所以将token保存在sessionStorage中
          window.sessionStorage.setItem("token", res.data.token)
          // 2. 通过编程式导航跳转到后台主页，路由地址必须是 /home
          this.$router.push("/home")
        })
      }
    }
  }
</script>

<style scoped>
  .login_box {
    width: 450px;
    height: 300px;
    background-color: #fff;
    border-radius: 10px;
    /* 居中显示 */
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
  }
  .avatar_box {
    height: 130px;
    width: 130px;
    border: 1px solid #eee;
    border-radius: 50%;
    box-shadow: 0 0 10px #ddd;
    /* 移动一半距离 */
    position: absolute;
    left: 50%;
    /* 移动图片一半的距离(x,y) */
    transform: translate(-50%, -50%);
  }
  .avatar_box img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
  }
  .login_from {
    position: absolute;
    bottom: 0;
    width: 100%;
    /* 左右20，上下0 */
    padding: 0 40px;
    box-sizing: border-box;
  }
  .btn {
    display: flex;
    /* 横轴上滞后 */
    justify-content: flex-end;

  }
</style>